DE 10 2004 023 886 A1 has disclosed a method and device for refining flexibly rolled band material. In the manufacture of flexibly rolled band material, the material thickness of the band is periodically changed in order to produce the starting material for individual sheet bars in a continuous process, which material has material thicknesses adapted as required to the sheet metal components to be manufactured from it. After successful rolling, the band material is first wound into a coil. A heat treatment generally takes place in the wound coil. Then, the band is unwound from the coil again, subjected to a surface treatment, and wound back into a coil. Only after this, in another procedure, are individual sheet bars cut from it and processed into individual sheet metal components. Since this procedure is complex and the surface treatment is not optimal due to the different material thicknesses of the band material, the object of DE 10 2004 023 886 A1 is to provide an improved method and a device adapted to it with which it is possible to simplify and improve the refining of the flexibly rolled band material. The intent is to attain this object by virtue of the fact that the band is manufactured as a flexibly rolled band material, is wound into a coil, unwound from it again, and then heat-treated and hot-dip galvanized in a uniform, continuous passage through a treatment line composed of an annealing section, a quenching unit, a preheating unit, and a zinc bath. To this end, a continuous furnace with an annealing section, a quenching section, a preheating unit, and a zinc bath is provided, along with a blast nozzle at the end. The galvanization occurs at 470° to 500° C., with the intent being for part of the energy used for the preceding heat treatment to be also used for the galvanization procedure. Optionally, in a blast unit downstream of the zinc bath, excess adhering zinc is blasted from the band material in order to achieve a precisely set coating thickness; the band thickness is likewise determined and used to control the spacing of the nozzle.
DE 10 2005 031 461 A1 has disclosed a method for manufacturing a micro-alloyed cold band with a property profile that is matched to the thickness progression; a hot steel band with an essentially homogeneous thickness and strength is rolled to form a cold band with an essentially constant band thickness using roll-down gradients in the range between 5 and 60%, an annealing treatment of the cold band is carried out at a temperature between 500° and 600° C., and a second rolling of the cold band is carried out in which the rolling is executed flexibly so that predefined thickness progressions are set, with a region of greater thickness and a region of lesser thickness, and finally, a second annealing treatment is carried out.
EP 1 074 317 B1 has disclosed a method for flexibly rolling a metal band in which during the rolling process, the metal band is conveyed through a rolling nip between two working rollers and during the rolling process, the rolling nip is intentionally moved in order to produce different band thicknesses over the length of the metal band. This flexible rolling is characterized in that during the rolling process, the rolling nip is intentionally moved, resulting in different-length band sections being rolled with different band thicknesses that can be connected to one another via different slopes. The goal of the flexible rolling is to manufacture rolled products with cross-sectional forms that are optimized in terms of load and weight. EP 1 074 317 B1 proposes an improved process guidance for flexible rolling in order to produce a metal band with an improved flatness even in wide bands.
EP 1 080 800 B1 has likewise disclosed a method for flexible rolling that corresponds essentially to the above-mentioned method; a temperature influence acting on the metal band is compensated for during the rolling in order to avoid deviations from the desired thickness and/or desired length of the individual band sections with a predetermined final temperature of the metal band.
EP 1 181 991 A2 has also disclosed a method and a device for the flexible rolling of a metal band to enable simple production of an asymmetrical band thickness profile.
The object of the present invention is to produce flexibly rolled, corrosion-protected sheets for the press hardening method, which are significantly easier to manufacture than before.